National Instruments 24-Bit Half/Full-Bridge Analog Input Module NI 9237 Operating Instructions Manual page 4

Caution
suitability for Class I, Division 2.
Caution
in an enclosure rated to at least IP 54 as defined by
IEC 60529 and EN 60529.
Caution
be within the following limits:
Capacitance .......................... 0.2 μF max
Inductance ............................ 80 mH max
Special Conditions for Hazardous Locations Use in Europe
This equipment has been evaluated as EEx nC IIC T4 equipment
under DEMKO Certificate No. 03 ATEX 0324020X. Each module
is marked
locations. If you are using the NI 9237 in Gas Group IIC hazardous
locations or in ambient temperatures of –40 °C ≤ Ta ≤ 70 °C, you
must use the device in an NI chassis that has been evaluated as
EEx nC IIC T4, Ex nA IIC T4, or Ex nL IIC T4 equipment.
NI 9237 Operating Instructions and Specifications
Substitution of components may impair
For Zone 2 applications, install the system
For Zone 2 applications, connected signals must
II 3G and is suitable for use in Zone 2 hazardous
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